<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <link rel="stylesheet" href="./css/demo4.css">
    <style>
        .div1 {
            font-weight: 900;
        }

        .div7 {
            box-sizing: border-box;
            width: 200px;
            height: 200px;
            border-bottom: 100px solid red;
            border-top: 100px solid rgb(52, 151, 39);
            border-left: 100px solid rgb(17, 0, 255);
            border-right: 100px solid rgb(0, 255, 42);
        }
    </style>
</head>

<body>
    <div class="div1">字体1</div>
    <div id="div2">字体2</div>
    <div class="div3">字体3</div>
    <div class="div4">字体4</div>
    <div class="div5" style="text-indent: 2em;">字体5</div>
    <div class="div6">字体6</div>
    <div class="div7"></div>

</body>

</html>